A crack-resistant and corrosion-resistant concrete and a method for producing the same

Abstract

The application relates to the technical field of concrete production, and particularly discloses an anti-cracking and anti-corrosion concrete and a production method thereof. The anti-cracking and anti-corrosion concrete is prepared from the following components in parts by weight: 250-320 parts of sulphoaluminate cement, 700-850 parts of gravel, 350-450 parts of sand, 110-190 parts of kaolin, 60-130 parts of blast furnace slag, 20-50 parts of feldspar powder, 20-40 parts of composite fiber, 8-20 parts of corrosion inhibitor and 150-200 parts of water; the composite fiber comprises polypropylene fiber, glass fiber and carbon fiber; the corrosion inhibitor is sodium diisooctyl sulfosuccinate and hydroxypropyl distarch phosphate coated calcium ammonium nitrate. The composite fiber and the corrosion inhibitor are added into the raw materials for preparing the concrete, the corrosion speed of chloride ions is slowed down, and the anti-cracking performance and the anti-corrosion performance of the concrete are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of concrete production, and particularly relates to a crack-resistant and corrosion-resistant concrete and a production method thereof. BACKGROUND

[0002] Concrete is one of the most important civil engineering materials in the contemporary era. It is a kind of artificial stone which is made of cementitious materials, granular aggregates, water, and, if necessary, additives and admixtures, according to certain proportions, uniform stirring, compaction, and curing hardening.

[0003] When concrete is applied to the construction of coastal areas or saline areas, chloride ions in the soil or seawater will erode the concrete, penetrate the surface of the steel bar, reduce the pH value of the surface of the steel bar, and destroy the passivation film on the surface of the steel bar, thereby accelerating the corrosion of the steel bar, affecting the bonding performance between the concrete and the steel bar, and accelerating the emergence of cracks in the concrete under the action of load, and reducing the effective bearing area of the reinforced concrete.

[0004] At present, in order to improve the corrosion resistance of concrete, substances such as fly ash, air entraining agent, and expansive agent are usually added to the concrete to change the internal structure of the concrete, thereby improving the corrosion resistance of the concrete. However, as the use time of the concrete is prolonged, chloride ions will continue to migrate to the interior of the concrete, and the corrosion resistance will decrease rapidly. Therefore, there is an urgent need to produce a concrete with better corrosion resistance and longer service life. SUMMARY

[0005] In order to improve the corrosion resistance of concrete and reduce the generation of cracks, the present application provides a crack-resistant and corrosion-resistant concrete and a production method thereof. The present application adds composite fibers and corrosion inhibitors to the raw materials for preparing the concrete. The composite fibers can enhance the toughness of the concrete, and the corrosion inhibitors can react with chloride ions to slow down the erosion rate of the chloride ions, thereby improving the crack resistance and corrosion resistance of the concrete.

[0006] In a first aspect, the present application provides a crack-resistant and corrosion-resistant concrete, which adopts the following technical scheme:

[0007] A crack-resistant and corrosion-resistant concrete, according to weight parts, the raw materials for preparing the concrete include the following components: 250-320 parts of sulphoaluminate cement, 700-850 parts of crushed stone, 350-450 parts of sand, 110-190 parts of kaolin, 60-130 parts of blast furnace slag, 20-50 parts of feldspar powder, 20-40 parts of composite fibers, 8-20 parts of corrosion inhibitors, and 150-200 parts of water;

[0008] The composite fibers include polypropylene fibers, glass fibers, and carbon fibers.

[0009] The corrosion inhibitor is sodium diisooctyl sulfosuccinate and ammonium calcium nitrate coated with hydroxypropyl distarch phosphate.

[0010] By adopting the technical scheme, the hydration product of the sulphoaluminate cement contains C-S-H gel, which can increase the compactness of the concrete and prevent the erosion of chloride ions; the gravel and sand are basic aggregates of the concrete, which can provide good compressive strength for the concrete; the particle sizes of the kaolin, the blast furnace slag and the feldspar powder are different, and the three can be compounded to fill the gaps between the gravel particles and the sand particles, further enhancing the compactness of the concrete and improving the impermeability thereof, wherein the kaolin has high specific surface area and adsorption capacity, which can adsorb harmful ions and moisture in the concrete, thereby improving the corrosion resistance of the concrete, and the iron element in the blast furnace slag can improve the durability of the concrete.

[0011] When the concrete is subjected to external force, the composite fibers can act as a bridge to prevent the expansion of cracks, thereby reducing the probability of chloride ions entering the interior of the concrete. Among them, the polypropylene fiber can improve the toughness and crack resistance of the concrete, and reduce the cracking and damage of the concrete; the glass fiber has good chemical stability and corrosion resistance, and can effectively resist the erosion of moisture and chloride ions; and the carbon fiber has a large aspect ratio, which can promote the dispersibility of the polypropylene fiber and the glass fiber in the concrete, and is also beneficial to improving the adhesion of the fiber concrete, and the three can be compounded to further improve the corrosion resistance of the concrete.

[0012] When the concrete is eroded by chloride ions, the calcium ions and ammonium ions can be released after the corrosion inhibitor is dissolved, and these ions can react with chloride ions to form insoluble calcium chloride and ammonium chloride, thereby reducing the corrosion effect of chloride on the steel bars.

[0013] As a preferred embodiment, the preparation raw materials of the concrete include the following components by weight: sulphoaluminate cement 280-320 parts, gravel 750-800 parts, sand 380-420 parts, kaolin 130-160 parts, blast furnace slag 80-100 parts, feldspar powder 25-40 parts, composite fiber 20-40 parts, corrosion inhibitor 10-20 parts, and water 150-200 parts.

[0014] By adopting the technical scheme, the amount of each preparation raw material of the concrete is optimized, which can further block the erosion of chloride ions, improve the corrosion resistance of the concrete, and reduce the possibility of cracking of the concrete.

[0015] As a preferred embodiment, the mass ratio of the kaolin, the blast furnace slag and the feldspar powder is (4-6):(2-4):1.

[0016] By adopting the technical scheme, the particle sizes of the kaolin, the blast furnace slag and the feldspar powder are different, the mass ratio of the three is controlled in the range, the gaps between the gravel particles and the sand particles can be better filled, the compactness of the concrete is further enhanced, and the impermeability of the concrete is improved.

[0017] In some preferred embodiments, the mass ratio of the kaolin, the blast furnace slag and the feldspar powder can be 5:3:1, 4:4:1 or 6:2:1, etc.

[0018] Preferably, the mass ratio of the polypropylene fiber, the glass fiber and the carbon fiber is 1:(3-5):(1-3).

[0019] By adopting the technical scheme, the mass ratio of the polypropylene fiber, the glass fiber and the carbon fiber is further adjusted, the dispersibility of the polypropylene fiber and the glass fiber in the concrete is promoted by the carbon fiber, and therefore the crack resistance and the corrosion resistance of the concrete are improved.

[0020] In some preferred embodiments, the mass ratio of the polypropylene fiber, the glass fiber and the carbon fiber can be 1:4:2, 1:3:3 or 1:5:1, etc.

[0021] Preferably, the corrosion inhibitor is prepared by the following steps:

[0022] S1, sodium diisooctyl sulfosuccinate and hydroxypropyl distarch phosphate are added to water, mixed uniformly, and a wall material mixture is prepared; S2, calcium ammonium nitrate is added to the wall material mixture and mixed uniformly, and spray drying is performed to prepare the corrosion inhibitor.

[0023] By adopting the technical scheme, sodium diisooctyl sulfosuccinate can reduce the surface tension of the solution and improve the wettability of calcium ammonium nitrate, hydroxypropyl distarch phosphate has good film-forming property and viscosity, and the two are compounded to coat the calcium ammonium nitrate, so that a slow-release film is formed on the surface of the calcium ammonium nitrate, the action time is prolonged, the dispersibility of the calcium ammonium nitrate is improved, the calcium ammonium nitrate can be uniformly dispersed in the concrete, and the corrosion resistance of the concrete is further improved.

[0024] In some specific embodiments, in step S1, the total mass of sodium diisooctyl sulfosuccinate and hydroxypropyl distarch phosphate is 6% of the mass of water.

[0025] Preferably, the mass ratio of the sodium diisooctyl sulfosuccinate and the hydroxypropyl distarch phosphate is (3-5):1.

[0026] By adopting the technical scheme, further adjustment of the mass ratio of sodium diisooctyl sulfosuccinate and hydroxypropyl distarch phosphate helps to improve the dispersibility of calcium ammonium nitrate, prolong the action time of calcium ammonium nitrate, and further slow down the erosion speed of chloride ions on concrete.

[0027] In some preferred embodiments, the mass ratio of sodium diisooctyl sulfosuccinate and hydroxypropyl distarch phosphate can be 3:1, 4:1 or 5:1, etc.

[0028] As preferred: in step S2, 30-70 mL of wall material mixed solution is added per 1 g of the calcium ammonium nitrate.

[0029] By adopting the technical scheme, if the amount of the wall material mixed solution used is too small, the calcium ammonium nitrate cannot be completely coated, resulting in poor dispersibility and slow-release effect of the corrosion inhibitor; if the amount of the wall material mixed solution used is too large, the slow-release film coated on the calcium ammonium nitrate can be relatively thick, causing the calcium ammonium nitrate to be unable to react with chloride ions in time, poor effect of slowing down the erosion speed of chloride ions, and increased production cost.

[0030] In some specific embodiments, in step S2, 50 mL of wall material mixed solution is added per 1 g of the calcium ammonium nitrate.

[0031] In a second aspect, the application provides a production method of anti-cracking and anti-corrosion concrete, which adopts the following technical scheme:

[0032] The production method of anti-cracking and anti-corrosion concrete comprises the following steps:

[0033] T1, uniformly mixing the polypropylene fiber, glass fiber and carbon fiber to obtain the composite fiber;

[0034] T2, uniformly mixing the sulphoaluminate cement, gravel, sand, kaolin, blast furnace slag, feldspar powder, composite fiber, corrosion inhibitor and water to obtain the concrete.

[0035] By adopting the technical scheme, the preparation method of the concrete is simple and easy to produce, can slow down the erosion speed of chloride ions, improve the anti-corrosion performance of the concrete, reduce the generation of cracks, and has a good market prospect.

[0036] In summary, the application has at least one of the following beneficial technical effects:

[0037] 1. The polypropylene fiber, glass fiber and carbon fiber are compounded in the application, the polypropylene fiber can improve the toughness of the concrete, the glass fiber can improve the anti-corrosion performance and chemical stability of the concrete, and the carbon fiber can promote the polypropylene fiber and glass fiber to be uniformly dispersed in the concrete, thereby improving the anti-cracking performance and anti-corrosion performance of the concrete together;

[0038] 2、The application uses sodium diisooctyl sulfonate succinate and hydroxypropyl distarch phosphate to coat calcium ammonium nitrate, sodium diisooctyl sulfonate succinate has good dispersibility, hydroxypropyl distarch phosphate has good film-forming property and viscosity, and the combination of the two can form a slow-release film on the surface of calcium ammonium nitrate, which not only prolongs the action time, but also improves the dispersibility of calcium ammonium nitrate, so that it can be uniformly dispersed in concrete, further improving the corrosion resistance of concrete. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 The preparation flow chart of the corrosion inhibitor in the concrete of the application;

[0040] Figure 2 The production flow chart of the concrete of the application. DETAILED DESCRIPTION

[0041] In order to make the application easier to understand, the application will be further described in detail below in combination with examples, which only serve to illustrate the application and are not limited to the scope of the application. The raw materials or components used in the application can be prepared by commercial means or conventional methods if not specifically stated.

[0042] Source of raw materials

[0043] Sulphoaluminate cement, loss on ignition 0.002%, compressive strength 42.5 MPa, cement fineness 0.002%; gravel, water content 0.1%, clay content 0.1%, compressive strength 5 MPa; sand, water content 0.1%, clay content 0.1%, grade first class; kaolin, water content ≤3%, whiteness 95%, grade first class; blast furnace slag, water content 0.1%, clay content 0.1%, compressive strength 7 MPa; feldspar powder, Na2O content 2%, SiO2 content 21%, Al2O3 content 35%, Fe2O3 content 10%, particle size 100 mesh; polypropylene fiber, fiber diameter 13±5 μm, average length 9 mm, water absorption rate ≤2%; glass fiber, fiber diameter 9-13 μm, length 3-30 mm; carbon fiber, diameter 2-10 μm, length 3-6 mm, carbon content 99.9%; hydroxypropyl distarch phosphate, CAS number 53124-00-8, effective ingredient content 99%, grade superior product.

[0044] Preparation Example 1:

[0045] Reference Figure 1The preparation method of the corrosion inhibitor in Preparation Example 1 is as follows: S1, 24 kg of sodium diisooctyl sulfosuccinate and 6 kg of hydroxypropyl distarch phosphate are added into 500 L of water, and mixed uniformly to prepare a wall material mixture; S2, 10 kg of calcium ammonium nitrate is added into 500 L of the wall material mixture and mixed uniformly, and then spray drying is performed to prepare the corrosion inhibitor. The spray drying conditions are as follows: the inlet air temperature is 170 ℃, the outlet air temperature is 130 ℃, the compressed air flow rate is 680 L / h, and the feeding speed is 7 ml / min.

[0046] In Preparation Example 1, the mass ratio of sodium diisooctyl sulfosuccinate to hydroxypropyl distarch phosphate is 4:1.

[0047] Preparation Example 2:

[0048] Preparation Example 2 differs from Preparation Example 1 in that the amount of sodium diisooctyl sulfosuccinate is 22.5 kg, and the amount of hydroxypropyl distarch phosphate is 7.5 kg, that is, the mass ratio of sodium diisooctyl sulfosuccinate to hydroxypropyl distarch phosphate is 3:1, and the rest is the same as in Preparation Example 1.

[0049] Preparation Example 3:

[0050] Preparation Example 3 differs from Preparation Example 1 in that the amount of sodium diisooctyl sulfosuccinate is 25 kg, and the amount of hydroxypropyl distarch phosphate is 5 kg, that is, the mass ratio of sodium diisooctyl sulfosuccinate to hydroxypropyl distarch phosphate is 5:1, and the rest is the same as in Preparation Example 1.

[0051] Preparation Example 4:

[0052] Preparation Example 4 differs from Preparation Example 1 in that 10 kg of calcium ammonium nitrate is mixed uniformly with 300 L of the wall material mixture, and the rest is the same as in Preparation Example 1.

[0053] Preparation Example 5:

[0054] Preparation Example 5 differs from Preparation Example 1 in that 10 kg of calcium ammonium nitrate is mixed uniformly with 700 L of the wall material mixture, and the rest is the same as in Preparation Example 1.

[0055] Comparative Preparation Example 1:

[0056] Comparative Preparation Example 1 differs from Preparation Example 1 in that the amount of sodium diisooctyl sulfosuccinate is 0 kg, and the amount of hydroxypropyl distarch phosphate is 30 kg, and the rest is the same as in Preparation Example 1.

[0057] Comparative Preparation Example 2:

[0058] Comparative Preparation Example 2 differs from Preparation Example 1 in that the amount of sodium diisooctyl sulfosuccinate is 30 kg, and the amount of hydroxypropyl distarch phosphate is 0 kg, and the rest is the same as in Preparation Example 1.

[0059] Example 1:

[0060] The preparation raw materials and their dosages of the concrete in Example 1 are shown in Table 1, wherein the corrosion inhibitor is selected from the corrosion inhibitor prepared in Preparation Example 1, the mass ratio of kaolin, blast furnace slag and feldspar powder is 5:3:1, and the mass ratio of polypropylene fiber, glass fiber and carbon fiber is 1:4:2. Referring to Figure 2 , the production method of the concrete is as follows: T1, the polypropylene fiber, glass fiber and carbon fiber are mixed uniformly to obtain a composite fiber; T2, the sulphoaluminate cement, gravel, sand, kaolin, blast furnace slag, feldspar powder, composite fiber, corrosion inhibitor and water are mixed uniformly to obtain the concrete.

[0061] Examples 2-3:

[0062] Examples 2-3 are different from Example 1 in that the dosages of the preparation raw materials of the concrete are different, and the specific dosages are shown in Table 1. The rest is the same as Example 1.

[0063] Examples 4-5:

[0064] Examples 4-5 are different from Example 1 in that the dosages of kaolin, blast furnace slag and feldspar powder in the concrete are different, and the specific dosages are shown in Table 1. In Examples 4-5, the mass ratio of kaolin, blast furnace slag and feldspar powder is 4:4:1 and 6:2:1 respectively, and the rest is the same as Example 1.

[0065] Examples 6-7:

[0066] Examples 6-7 are different from Example 1 in that the dosages of polypropylene fiber, glass fiber and carbon fiber in the concrete are different, and the specific dosages are shown in Table 1. In Examples 6-7, the mass ratio of polypropylene fiber, glass fiber and carbon fiber is 1:3:3 and 1:5:1 respectively, and the rest is the same as Example 1.

[0067] Table 1. Preparation raw materials and their dosages (kg) of the concrete in Examples 1-7

[0068]

[0069] Examples 8-11:

[0070] Examples 8-11 are different from Example 1 in that the corrosion inhibitor in the concrete is selected from the corrosion inhibitors prepared in Preparation Examples 2-5 respectively, and the rest is the same as Example 1.

[0071] Comparative Example 1:

[0072] Comparative Example 1 is different from Example 1 in that the dosage of polypropylene fiber in the concrete is 0, the dosage of glass fiber is 14 kg, and the dosage of carbon fiber is 14 kg, and the rest is the same as Example 1.

[0073] Comparative Example 2:

[0074] Comparative Example 2 differs from Example 1 in that the polypropylene fiber content in the concrete is 7 kg, the glass fiber content is 0 kg, and the carbon fiber content is 21 kg, and the rest is the same as Example 1.

[0075] Comparative Example 3:

[0076] Comparative Example 3 differs from Example 1 in that the polypropylene fiber content in the concrete is 7 kg, the glass fiber content is 21 kg, and the carbon fiber content is 0, and the rest is the same as Example 1.

[0077] Comparative Example 4:

[0078] Comparative Example 4 differs from Example 1 in that the corrosion inhibitor is calcium nitrate, which is not coated with sodium diisooctyl succinate sulfonate and hydroxypropyl distarch phosphate, and the rest is the same as Example 1.

[0079] Comparative Examples 5-6:

[0080] Comparative Examples 5-6 differ from Example 1 in that the corrosion inhibitor is selected from the corrosion inhibitors prepared in Comparative Preparation Examples 1-2, respectively, and the rest is the same as Example 1.

[0081] Test Example:

[0082] The concrete produced in Examples 1-11 and Comparative Examples 1-6 was tested for performance, including 28d chloride ion migration coefficient, early crack resistance, and compressive strength. The 28d chloride ion migration coefficient and early crack resistance were tested in accordance with GB / T50082-2009 "Standard Test Methods for Long-Term Performance and Durability of Ordinary Concrete", the early crack resistance was evaluated by the total cracking area per unit area, and the compressive strength was tested in accordance with GB / T 50081-2002 "Standard Test Methods for Mechanical Properties of Ordinary Concrete", and the specific test data is shown in Table 2.

[0083] Table 2

[0084]

[0085]

[0086] From the test results in Table 2, the 28d chloride ion migration coefficient of the concrete produced in Examples 1-11 and Comparative Examples 1-6 was 4.98-7.02 x 10 -12 m 2 / s, the total cracking area per unit area was 172-355 mm 2 / m 2 , and the compressive strength was 37.7-53.9 MPa.

[0087] From the test data of Examples 1-5, it can be seen that the concrete produced according to the raw materials and their amounts in Example 1 can effectively block the erosion of chloride ions, and has good toughness and strength, and can be applied to the construction of coastal areas or saline areas. In addition, the mass ratio of kaolin, blast furnace slag and feldspar powder has a certain influence on the crack resistance and corrosion resistance of the concrete, and when the mass ratio of kaolin, blast furnace slag and feldspar powder is 5:3:1, the concrete has stronger resistance to chloride ion erosion and better crack resistance.

[0088] From the test data of Examples 1, 6-7 and Comparative Examples 1-3, it can be seen that when polypropylene fibers, glass fibers and carbon fibers are added to the concrete together, they will have a synergistic effect, significantly improving the toughness of the concrete and reducing the occurrence of cracks on the concrete. Especially when the mass ratio of polypropylene fibers, glass fibers and carbon fibers is 1:4:2, the synergistic effect between them is better.

[0089] From the test data of Examples 1, 8-11 and Comparative Examples 4-6, it can be seen that after the calcium ammonium nitrate is coated with sodium diisooctyl succinate sulfonate and hydroxypropyl distarch phosphate, the resistance of the concrete to chloride ion erosion is significantly improved, which may be due to the fact that the dispersion of the calcium ammonium nitrate is improved after coating, and it can be uniformly dispersed in the concrete. Moreover, the combination of sodium diisooctyl succinate sulfonate and hydroxypropyl distarch phosphate can further improve the performance of calcium ammonium nitrate in slowing down the erosion speed of chloride ions, thereby further improving the corrosion resistance of the concrete and reducing the possibility of cracking of the concrete.

[0090] It should be noted that the above-described examples are only used to explain the present application and do not constitute any limitation on the present application. The present application has been described by referring to typical examples, but it should be understood that the words used therein are descriptive and explanatory words, rather than limiting words. The present application can be modified as specified within the scope of the claims of the present application, and the present application can be revised within the scope and spirit of the present application. Although the present application described therein relates to specific methods, materials and examples, it does not mean that the present application is limited to the specific examples disclosed therein, on the contrary, the present application can be extended to all other methods and applications with the same function.

Claims

1. A crack-resistant and corrosion-resistant concrete, characterized in that: The raw materials for preparing the concrete, by weight, include the following components: 250-320 parts sulfoaluminate cement, 700-850 parts crushed stone, 350-450 parts sand, and 110-190 parts kaolin. 60-130 parts blast furnace slag, 20-50 parts feldspar powder, 20-40 parts composite fiber, 8-20 parts corrosion inhibitor and 150-200 parts water; The composite fibers include polypropylene fibers, glass fibers, and carbon fibers; The corrosion inhibitor is sodium diisooctyl succinate sulfonate and calcium ammonium nitrate coated with hydroxypropyl distarch phosphate; The mass ratio of the polypropylene fiber, glass fiber and carbon fiber is 1:(3-5):(1-3). The corrosion inhibitor is prepared by the following steps: S1. Sodium diisooctyl succinate sulfonate and hydroxypropyl distarch phosphate are added to water and mixed evenly to prepare a wall material mixture. S2. Add calcium ammonium nitrate to the wall material mixture and mix evenly, then spray dry to obtain the corrosion inhibitor.

2. The crack-resistant and corrosion-resistant concrete according to claim 1, characterized in that: The raw materials for preparing the concrete, by weight, include the following components: 280-320 parts of sulfoaluminate cement, 750-800 parts of crushed stone, 380-420 parts of sand, 130-160 parts of kaolin, 80-100 parts of blast furnace slag, 25-40 parts of feldspar powder, 20-40 parts of composite fiber, 10-20 parts of corrosion inhibitor, and 150-200 parts of water.

3. The crack-resistant and corrosion-resistant concrete according to claim 1, characterized in that: The mass ratio of the kaolin, blast furnace slag and feldspar powder is (4-6):(2-4):

1.

4. The crack-resistant and corrosion-resistant concrete according to claim 1, characterized in that: The mass ratio of sodium diisooctyl succinate sulfonate to hydroxypropyl distarch phosphate is (3-5):

1.

5. The crack-resistant and corrosion-resistant concrete according to claim 1, characterized in that: In step S2, each 1g of the calcium ammonium nitrate is added to 30-70mL of the wall material mixture.

6. A method for producing crack-resistant and corrosion-resistant concrete as described in any one of claims 1-5, characterized in that: Includes the following steps: T1. The polypropylene fiber, glass fiber and carbon fiber are mixed evenly to obtain the composite fiber; T2. Mix the sulfoaluminate cement, crushed stone, sand, kaolin, blast furnace slag, feldspar powder, composite fiber, corrosion inhibitor and water evenly to prepare the concrete.

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